The present invention relates to a brake system for bicycles, and more particularly, to an anti-brake system for bicycles.
A conventional disk brake system for bicycles is shown in FIG. 1 and generally includes an arm 1, a clamp assembly 2 and a brake cable 3. Although the disk brake system is welcomed by the users for its stable and sharp braking, it could brake too sharp so that the rider cannot control the bicycle especially when the bicycle is ridden at a high speed. The initial force makes the rider to fall if the brake system is activated too sharp.
The present invention intends to provide a disk brake system wherein the disk is not clamped during braking so as to reduce the initial force applied to the riders.
In accordance with one aspect of the present invention, there is provided a brake system connected to a front fork or seat stays and activated by a brake cable so as to clamp a disk. The brake system comprises a frame located on a side of the disk and a rack is arranged on a side of the frame. A positioning member is fixed to the front fork or the seat stays. A clamping assembly is movably connected onto the disk and operatively connected to the frame and the positioning member. The clamping assembly includes a clamp member which has a slot in which the disk is received therein. A passage is defined in the clamp member and two blocks are located below the passage. An activation member is slidably received in the passage of the clamp member and is connected to the frame. A groove is defined in each of two sides of the activation member and two springs are received in the two grooves. One of tow ends of each of the springs is engaged with a protrusions extending from an insides of each of the grooves, and the other end of each of the springs contacts the blocks. A pawl is located in the clamp member and includes teeth engaged with the rack. A plurality of beads are installed at a side of the pawl. A main shaft is located in the clamp member and between a side of the disk and the pawl. A plurality of tear-shaped recesses are defined in a side of the disk portion and each recess includes a shallow portion and a deep portion. The beads are movably received in the recesses. An adjusting cover is located in the clamp member and on the other side of the disk. Two linings are located on the two sides of the disk and between the main shaft and the adjusting cover. The linings may clamp the disk when the brake cable is pulled.
The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.